Apparatus for delivering dry steam proportionately over extended areas of an upwardly traveling pulp mat



1968 J. H. DUPASQUIER 3,352,084

APPARATUS FOR DELIVERING DRY STEAM PROPORTIONATELY OVER EXTENDED AREAS OF AN UPWARDLY TRAVELING PULP MAT Filed Sept. 26, 1966 2 Sheets-Sheet 1 INVENTOR. JOSEPH H. DUPASQUIER ATTORNEY Jan. 9, 1968 J. H. DUPASQUIER 3,3 2,

APPARATUS FOR DELIVERING DRY STEAM PROPORTIONATELY OVER EXTENDED AREAS OF AN UPWARDLY TRAVELING PULP MAT Filed Sept. 26, 1966 2 Sheets-Sheet 2 n v N m Tr to (\J N O p ("7 I Q i q- INVE R. JOSEPH H. DUP QUIER ATTORNEY United States Patent APPARATUS FOR DELIVERING DRY STEAM PRO- PGRTIONATELY OVER EXTENDED AREAS OF AN UPWARDLY TRAVELING PULP MAT Joseph H. Dupasquier, 5855 NW. Skyline Drive, West Linn, Oreg. 97068 Filed Sept. 26, 1966, Ser. No. 582,000 Claims. (Cl. 34-60) This invention is concerned in general with the application of dry steam to the traveling pulp mat on a paper machine, mainly for the purpose of heating the pulp mat and thereby increasing the rate of the withdrawal of water therefrom. The advantages obtained by the application of heat to the pulp mat through the medium of dry steam are well known. I

The device of the present invention is similar in some respects to that described in United States Letters Patent No. 3,242,587, issued under date of Mar. 29, 1966, entitled, Apparatus for Concentrating a Blanket of Dry Steam for an Extended Area on a Pulp Mat. However, the device in the said patent, while functioning satisfactorily when employed on a pulp mat moving in a path which is not inclined too much from the horizontal, has been found less satisfactory for use in locations where the path of the pulp mat is more nearly vertical, and it is often advantageous to be able to apply heating and dryin g steam to the mat in such locations also.

Accordingly, an object of the present invention is to provide certain improvements in an apparatus of the type described in said U.S. Letters Patent No. 3,242,587, which will enable the application of dry steam to the mat to be carried out more effectively, particularly under such conditions as above indicated.

In cases where the pulp mat is in considerable width, the moisture condition of the mat will usually not be uniform across the entire width of the mat. For example, as is generally known, the edge portions of the mat tend to lose moisture more rapidly than the center portions. Therefore, a related object of this invention is to provide an improved apparatus for concentrating drying steam on an upwardly traveling pulp mat with which the application of the steam can be proportionately controlled in the respective areas across the mat if and when desired.

An additional object is to provide an improved apparatus for concentrating dry steam on an upwardly traveling pulp mat which will be simple and practical to operate and maintain.

The construction and manner of operation of the apparatus employed in carrying out this invention will be readily understood from the following description and explanation with reference to the accompanying drawings, wherein:

FIG. 1 is a side elevation of the apparatus illustrating the apparatus mounted in position adjacent an upwardly traveling pulp mat, with a portion of the near side of the apparatus broken away for clarity;

FIG. 2 is a foreshortened elevation taken on line 22 of FIG. 1 drawn to a smaller scale;

FIG. 3 is a fragmentary and foreshortened sectional elevation taken on the line indicated at 3-3 in FIG. 1;

FIG. 4 is a fragmentary, more or less diagrammatic, plan view on line 4--4 of FIG. 3 drawn to a smaller scale;

FIG. 5 is a section on line 55 of FIG. 3;

FIG. 6 is a section on line 6-6 of FIG. 3;

FIG. 7 is a foreshortened section taken on line 7-7 of FIG. 2 drawn to a smaller scale; and

FIG. 8 is a fragmentary and schemtic perspective view showing how the condensate drained off from each side of the apparatus is conveniently collected for disposal or further use.

Referring first to FIGS. 1 and 2, the device includes the 3,362,084 Patented Jan. 9, 1968 first main housing 10 which is cylindrical in shape and of sufiicient length to extend transversely across the entire width of the pulp mat; and a second housing 11 attached to and extending upwardly from the housing 10 along the path of the mat, having a width equal to the length of the first housing 10. The housing 11 comprises a pair of identical side walls, one of which 12 is shown in FIG. 1, secured to the end walls of housing 10 respectively, and a back wall 13 shaped as shown in FIG. 1. The back wall 13 is reinforced by a pair of external gussets 14. The housing 11 is entirely open on the side facing the pulp mat. In FIGS. 1 and 2 the pulp mat is indicated at M and is traveling upwardly between lower and upper suction rolls R1 and R2 and thus traveling in the direction indicated by the arrow X in FIG. 1.

The housing 10 (FIG. 3) is closed by end walls 15 and 16 which are provided with openings through which steam pipes extend. The housing 10 is formed into a series of steam-collecting chambers, thus three in the apparatus as illustrated in the drawings, by the partition walls 17 and 18, and these three chambers are designated as A, B and C in FIG. 3. The number of steam pipes which extend longitudinally through the housing 10 is the same as the number of the steam-collecting chambers A, B and C and thus in the apparatus illustrated there are three steam pipes 19, 20 and 21,

Although these three steam pipes all extend the entire length of the housing 10 each pipe is so designed as to be capable of delivering steam into only one of the steamcollecting chambers in the housing 10. Each pipe is entirely cylindrical throughout its extent, except within the one chamber into which it discharges steam. In such chamber, the bottom of the pipe is formed with an inverted V- shaped section, the extent of which is restricted to that particular chamber, and a series of steam jet holes extend vertically downwardly through the ridge or vertex of this inverted V-shaped section. The arrangement is the same as that described in U.S. Letters Patent No, 3,037,706, issued under date of June 5, 1962, entitled Limitable Steam Shower Assembly to which reference should be made.

The housing 10 is provided with a top steam-discharging slot 22 (FIGS. 1, 3, 5 and 6) for each of the chambers A, B and C. These slots are in alignment and extend longitudinally along the housing. As indicated in FIGS. 1, 5 and 6, the slots 22 are so positioned on the housing 10 as to cause the steam from the respective steam-collecting chambers A, B and C to be discharged in a direction inclined obliquely upwardly toward the traveling ulp mat.

The upper or second housing 11 is also formed with a series of steam-dispensing chambers corresponding in number to the number of steam-collecting chambers in housing 10. These steam-dispensing chambers in housing 11 are designated A, B and C in FIGS. 3 and 7 and are formed by partition walls 23 and 24 which extend in the same vertical planes as the partition walls 17 and 18 respectively in the housing 10. The widths of the steamdispensing chambers A, B and C in housing 11 con sequently correspond respectively to the lengths of the cylindrical chambers A, B and C in housing 10 respectively.

Thus the steam collected in each of the chambers A, B or C in housing 10 will be discharged Only into the corresponding steam-dispensing chamber in housing 11, and the controlling of the delivery of steam separately into the chambers A, B and C of housing 10 makes it possible to control the dispensing of proportionate amounts of the drying steam concentrated onto the different areas of the traveling pulp mat. This is an important feature of the invention. As mentioned previously, since the edge portions of the traveling pulp mat tend to lose moisture more rapidly than the center portions, it is often desirable to subject the center portions of the mat to proportionately more treatment with drying steam in order to achieve a more equalized moisture cOndition across the entire mat. The present invention makes this possible. In addition to controlling the proportionate amounts of steam disposed by the separate steam-dispensing chambers, the number and relative sizes of these chambers, and of the corresponding steam-collectingchambers, could be changed. For example, in the ap paratus illustrated the steam-dispensing chamber B and its related steam-collecting chamber B have been made slightly larger than the other two chambers of each housing. However, it has also been found satisfactory to have the three chambers of each group of the same size since the regulating of the delivery of steam into the respective steam-collecting chambers enables the distribution of the drying steam onto the mat to be adequately proportioned.

Each of the steam pipes 1, 2t) and 21 is connected with a suitable source of steam under pressure, indicated schematically at S in FIG. 4, and suitable control valves 19, 20 and 21 control the passage of steam into the pipes 19, 20 and 21 respectively and thus control the delivery of steam into the steam-collecting chambers A, B and C and finally control the dispensing of steam through the medium of the dispensing chambers A, B and C respectively. The mounting of the steam pipes in the housing 10 is the same as that described in detail in US. Patent No. 3,037,706 above mentioned and thus need not be described more fully here.

Suitable drain outlets 25 (FIG. 3) are provided at each end of these pipes outside of the housing 10 to allow any water collecting in the pipes to be drained off. Drain hoses 25' lead from these outlets to a condensate collector mentioned later. Also the bottom of housing 10 is provided with drain holes 26 for the steam-collecting chambers A, B and C so as to drain off any water collecting in these chambers. These drain holes 26 discharge into the top of a drain housing 27 which is mounted on the housing 10 and extends longitudinally along the bottom of the housing 10 for the full length thereof. A separator wall 28, extending along the full length of the drain housing 27, divides it into upper and lower sections. The upper section in turn is divided into chambers, corresponding in length to the adjacent chambers A, B and C in housing 10 by the partitions 17 and 18 located in the same planes as the partitions 17 and 18 (FIG. 3). The separator wall 28 is provided with a single drain hole 29 for each of the chambers of the upper section in the housing 27. The partitions 17 and 18 do not extend down into the lower section of the housing 27 since there is no likelihood that any water which drains down finally through a lower hole 29 to collect in the lower section of the housing 27 could be forced back upwardly into an adjacent chamber. The lower section of housing 27 is provided with a suitable low pressure drain 30 at each end, and a hose leads from each drain to a condensate collector.

Due to the water drainage provided for each steam pipe, and to the fact that the steam is discharged downwardly from the steam jet holes in the ridges of the inverted V-sha ed sections in the pipes, and to the fact that the steam is first discharged downwardly into the steam-collecting chambers A, B and C of the housing 10, and that any water is immediately drained oif from the bottom of these chambers, the steam leaving these chambers through the top outlet slots 22 and passing into the steam-dispensing chambers A, B and C will be relatively dry, and no undesirable globules of water will be carried by the steam into the dispensing chambers for deposit on the pulp mat.

Since the steam pipes 19, 20 and 21 extend entirely through the housing 10 the heat from each pipe contributes to the heating of all three chambers A, B and C,

even though each pipe is restricted to the discharging of steam into one chamber only. It will be noted from FIGS. 1, 5 and 6 that one of the steam pipes, thus the steam pipe 19 as shown in the drawings, extends along in close proximity to the steam discharge slots 22. This pipe is positioned symmetrically with respect to these aligned slots so that there is a restricted and equal-sized passageway between both sides of the pipe and the adjacent slot 22 in each of the chambers. This interference with the steam as it is forced through the slots 22 aids having the steam in dry, hot condition when it arrives in the steam-dispensing chambers in the housing 11.

In the steam-dispensing chambers A, B and C the steam is confined to the corresponding areas on the pulp mat by the side walls 12 of the housing 11 and the partition walls 23 and 24 within the housing, all of which walls have their lower edges in close proximity to the pulp mat. The back wall 13 of the housing 11, as shown in FIG. 1, slopes first obliquely towards the pulp mat and then, follows along substantially parallel to the mat spaced a short distance from the mat. The dry steam is thus confined closely to the mat by the housing 11 for absorption into and for the heating of the mat almost up to the point where the mat reaches the nip at the upper suction roll R2. Consequently, in spite of the fact that the pulp mat is traveling upwardly and is in a position in which numerous other devices for applying drying steam to the that have not been found effective the apparatus of the present invention is able to keep the steam in contact with the mat over exended areas of the mat and also to provide for proportionate amounts of steam being delivered into different areas on the mat as desired, and with only a minimum waste of the steam.

The steam given off from the steam-dispensing chambers of the housing 11 which is not absorbed by the mat is delivered into the ingoing nip of the upper suction press roll. The momentum of the presses, and thus the speed at which the mat travels, will draw the steam into the nip where the steam will be pulled through the mat, thereby further increasing the temperature in the mat, changing the viscosity of the water and thus increasing drainage, all of which contributes to the delivery of a hotter sheet into the dryers; and, as is Well known, when a hotter sheet passes into the dryers less fuzzing takes place on the first few dryers.

FIG. 8, together with FIG. 3, illustrates how the condensate drained off from each side of the apparatus is conveniently collected. A hose 25 leads from each of the drain outlets 25 and a hose 30 leads from the low pressure drain 30. Each of the hoses 25 and 30 leads into a closed condensate collector 31 (through the intermediary of a suitable check valve such as a pneutrol check valve. A drain hose 32 leads from the condensate collector 31 and the collected condensate is either finally disposed of or put to further use.

I-claim:

1. An apparatus for selectively delivering concentrated dry steam onto an upwardly traveling pulp mat, said apparatus comprising a first housing, partition walls in said housing forming said housing into a plurality of steam-collecting chambers, a second housing connected with said first housing having a corresponding number of steam-dispensing chambers receiving steam from said collecting chambers in said first housing respectively, the partition walls between said chambers in said first housing and the partition walls between said chambers in said second housing located in the same vertical planes respectively, each of said steam-collecting chambers having an outlet leading into a corresponding steam-dispensing chamber, each of said steam-dispensing chambers extending longitudinally in the direction of travel of. the pulp mat and having an open side facing onto said pulp mat, means for separately delivering steam into each of said steam-collecting chambers and thereby selectively causing the delivery of steam into the corresponding dispensing chambers and steam to be dispensed from said dispensing chambers onto corresponding areas on said pulp mat, and means for draining water from the steam in said steam-collecting chambers.

2. The combination claimed in claim 1 With said outlets from said steam-collecting chambers into said steamdispensing chambers being in alignment transversely with respect to the direction of travel of the pulp mat and with said means for selectively delivering steam into each of said steam-collecting chambers consisting of a plurality of steam pipes extending entirely through said first housing, the number of said pipes corresponding to the number of said steam-collecting chambers, with steam supply means connected to each of said pipes, with a control valve and a water drain for each pipe, said steam pipes having steam discharging orifices and said orifices of said pipes restricted to steam-collecting chambers respectively.

3. The combination claimed in claim 2 with said steam pipes extending parallel to each other and in parallelism with the alignment of said outlets of said steam-collecting chambers, and With one of said pipes so positioned as to provide partial interference with the discharging of steam through said outlets of said steam-collecting chambers.

4. The combination claimed in claim 1 with said means for draining water from the steam in said steam-collecting chambers including a drain housing extending longitudinally along on the bottom of said first housing, a separator wall in said drain housing dividing said drain housing into an upper and a lower section, partition walls in said "uper section located in the same vertical planes respectively as the partition walls in said first housing and forming drain chambers in said upper section of said drain housing, said steam-collecting chambers in said first housing having drain holes leading down into the corresponding drain chambers in said upper section of said drain housing, each of said drain chambers in said upper section of said drain housing having a drain hole leading down into said lower section, and a drain outlet at an end of said lower section.

5. The combination claimed in claim 2 with said means for draining water from the steam in said collecting chambers including a drain housing extending longitudinally along on the bottom of said first housing, a separator wall in said drain housing dividing said drain housing into an upper and lower section, partition walls in said upper section of said drain housing located in the same vertical planes respectively as the partition walls in the said first housing and forming drain chambers in said upper section of said drain housing, said steam-collecting chambers in said first housing having drain holes leading down into the corresponding drain chambers in said upper section of said drain housing, each of said drain chambers in said upper section of said drain housing having a drain hole leading down into said lower section of said drain housing, and a drain outlet at the end of said lower section.

References Cited UNITED STATES PATENTS 1/1945 Bradner 341 14 9/1957 Brodie 34-422 WILLIAM J. WYE, Primary Examiner. 

1. AN APPARATUS FOR SELECTIVELY DELIVERING CONCENTRATED DRY STEAM ONTO AN UPWARDLY TRAVELING PULP MAT, SAID APPARATUS COMPRISING A FIRST HOUSING, PARTITION WALLS IN SAID HOUSING FORMING SAID HOUSING INTO A PLURALITY OF STEAM-COLLECTING CHAMBERS A SECOND HOUSING CONNECTED WITH SAID FIRST HOUSING HAVING A CORRESPONDING NUMBER OF STEAM-DISPENSING CHAMBERS RECEIVING STEAM FROM SAID COLLECTING CHAMBERS IN SAID FIRST HOUSING RESPECTIVELY, THE PARTITION WALLS BETWEEN SAID CHAMBERS IN SAID FIRST HOUSING AND THE PARTITION WALLS BETWEEN SAID CHAMBERS IN SAID SECOND HOUSING LOCATED IN THE SAME VERTICAL PLANES RESPECTIVELY, EACH OF SAID STEAM-COLLECTING CHAMBERS HAVING AN OUTLET LEADING INTO A CORRESPONDING STEAM-DISPENSING CHAMBER, EACH OF SAID STEAM-DISPENSING CHAMBERS EXTENDING LONGITUDINALLY IN THE DIRECTION OF TRAVEL OF THE PULP MAT AND HAVING AN OPEN SIDE FACING ONTO SAID PULP MAT, MEANS FOR SEPARATELY DELIVERING STEAM INTO EACH OF SAID STEAM-COLLECTING CHAMBERS AND THEREBY SELECTIVELY CAUSING THE DELIVERY OF STEAM INTO THE CORRESPONDING DISPENSING CHAMBERS AND STEAM TO BE DISPENSED FROM SAID DISPENSING CHAMBERS ONTO CORRESPONDING AREAS ON SAID PULP MAT, AND MEANS FOR DRAINING WATER FROM THE STEAM IN SAID STEAM-COLLECTING CHAMBERS. 